A mechanically inept noob enters the world of junior karting…

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It was supposed to be fairly straightforward: a lunchtime trip to see JC at Revolution and get the head volumes checked on both motors (to ensure there would be no surprises if did well enough to get scrutineered at the weekend). The practice motor was borderline and needed a thorough cleaning to get the head volume to a safe reading. The race motor was fine as far as the head volume was concerned but there was no longer any end play in the crank shaft. We opened up the crank halves; the pin had moved a fraction and the bearings weren’t spinning very freely at all. It wasn’t the news I really wanted to hear this close to the weekend. The race motor has been sat around since the last club round: I had had the head and barrel off for a visual inspection post-race but not noticed the lack of end play. Another learning for next time…

Fortunately, JC was able to sort everything out for me today and I collected the engines from him this evening but, with this and the weather, I’m a little behind where I would like to be if we are setting off for the track on Friday. Tomorrow evening will be a busy one :/

Today was the last weekend day before our belated reappearance and, with the kart stripped down to just a chassis with a brake system, I had no idea how long it would take to get sorted. I needed to touch up the paintwork having had the chassis welded and then it was just a case of putting everything else back together.

There were a few hiccups along the way – the steering rod seemed to have a little resistance when turning and so I spent some time replacing it all whilst trying to find out where the resistance was coming from (steering column bush was over-tightened although one of the saftey collars was also a little tight to the bush) and then I put the first track rod below the stub axle(!). I took the opportunity to refresh most of the bolts and T-Cut the undesirable bits and the kart looked much happier for a quick polish with Carlack 68 🙂 It was nice to have the newly rebuilt engine fitted, which had been waiting for me to collect since the beginning of the year. The biggest issue I had was right at the end of the day – the throttle was not closing fully despite the pedal hitting the stop bolt with nothing else having been moved. I spent some time trying to identify what had changed but ended up just adjusting the stop bolt. Eight hours later and, with darkness falling, it was finally done. The wife wasn’t impressed with my being late in for tea but I think we are there – I always find myself wondering if I have tightened everything/put it all back together properly so I’ll give it all another check in the week. Fingers crossed the weather isn’t too bad for the coming weekend.

I’ve spent every dry weekend day this month (admittedly, that isn’t that many) getting the kart sorted for our first outing of the year. Cleaning, checking seat fitting, replacing worn nuts and bolts, new axle, new sprocket carrier, replacing tyres on rims, changing the brake fluid – it looked like we were set for a potential return to the track this week. That was until a friend confirmed that the crack in the paintwork around the engine side bearing hanger was actually a crack in the chassis and would need welding 🙁 It is in a common spot for TKM karts, maybe I paid the price for running the engine stop bolt too close to the engine mount – because of my early problems with engine mounts, I had always backed the bolt off by 1mm or so but, as one of the other Dads pointed out, the vibration alone will likely negate that. The fact that my stop bolt was just a bare hex bolt, with no plastic head to dampen any vibration may not have helped. Or maybe it was just one of those things with a 5-year old chassis.

Anyway, that necessitated taking a half day to get the weld done at Brightweld – it doesn’t look *too* bad and I need to rub down the paintwork and paint the repaired area. Whilst I was there, I stopped off at Hobzie Motorsport to pick up a better engine stop bolt and he also delivered the good news that my 2009 EVR looks more like a 2008 EVXX!!! Great news, huh? :S

The icing on the cake was, of course, the inevitable rain that soaked the kart less than a mile from my house. Still hoping to make it out this weekend. The engine stop bolt might be a tad looser too…

Leaving home with this in the rear view mirror normally gives me a buzz. It’s a shame we were going to the welding shop. In the rain.

You know you are still operating as a noob mechanic when, having spent only five weeks away from karting, you spend 5 minutes looking at your sprocket carrier wondering which way around it goes on the axle!!! :S

It was good to start getting the kart ready today – we aren’t quite there yet as I still want to bleed the brakes, clean the exhaust cans and change lots of tyres. Really wanting to get out there now – eagerly looking forward to testing in a few weeks time 🙂

This month is proving to be one of those where the costs keep mounting. I have decided that I’ll buy new tyres from now on – I still have several sets of used slicks that we will race on although the two sets of used wets we bought in the summer have obviously degraded a fair bit and I wanted to get hold of a new set to give us something more suitable for a very wet track. I picked up an unused set of wets from one of the forums for £120. I also bought some brake fluid and replacement seals ahead of my bi-annual bleeding of the brakes and a new sprocket carrier from eBay in a bid to finally rid my chain of that tense spot (the reality is that it could still turn out to be the axle, which I’ll replace when funds improve, and I’ve probably stretched my nice Panther chain by now anyway).

Still to be funded are the engine rebuild, the MSA licenses (don’t start me on the rip-off PG license again – I will email my feelings on this to the MSA when I get a chance!), the club membership and track loyalty card.

After we raced at the start of December, the plan was to strip the kart, clean it and wrap it up for 6 weeks or so. Because I really don’t have the room (or the lighting) to make a proper job of this in the garage, the ability to do this depends entirely upon the weather. Factor in Christmas and a holiday period that consisted of exactly one dry day spent repairing storm damaged trees and I have to confess the kart has been untouched in over a month. Until yesterday.

The kart was dirty but I didn’t think it was wet and I didn’t expect to find quite so much rust on the axle, with spots forming on the bumper and seat supports. Worse, my expensive Panther chain was starting to rust also! With the wife working the weekend and two kids to entertain/taxi around, I wasn’t able to spend more as much time as I would have liked on it but I was able to strip the back end and clean most of it up. Wire wool and T-Cut got rid of all but the toughest rust spots on the axle; I could probably have gotten rid of the remainder had I not been working to a ‘pick up the wife from work’ deadline. To make myself feel a bit better about the neglect, I polished the chassis and bumper 🙂 Just need to do the same for the front half of the kart and change the brake fluid and we’ll be in a better position to consider karting again!

So we’re on the eve of our first race weekend!!! The overwhelming enthusiasm that saw me wishing most of this week would pass as quickly as possible has been dampened somewhat by the weather forecast. I do share a 6x3m awning with another Dad but his lad is a couple of months behind us from a competition-readiness perspective (or rather – he shares my view on not chucking them in until they are ready) and I don’t have the space in the Clio or the trailer to bring it with us. We’re going to have to stick it out if it gets very wet although working out the back of a Clio in heavy rain is no fun I can assure you.

Having only just seen the worsened forecast, I got to the camping shop 15 mins before closing this afternoon to try to get some waterproofs. Unfortunately I arrived as the shop keeper was getting into her car having decided to call it a day and, after watching me for a few mins (presumably making sure I wasn’t about to throw a dustbin through the window and help myself), she wound down her window, told me she had just put the alarm on and that I’d have to come back. Customer service, anyone? :/

Anyway the past few weekends have been all about getting set for the race. It’s been an expensive time what with the repairs after throwing a chain and I’ve also bought several sets of used slicks that each had a day’s wear (I figure we’ll race on used tyres at least for the three meetings we plan to do this year), a set of Doulgas SE rims (I wanted another set of rims to avoid having to change tyres overnight between the practice and race days) and a couple of additions for the toolkit (deep 10mm sprocket, front sprocket remover). As far as actually doing things is concerned, the maintenance has gone something like this: new front and rear sprockets fitted, chain guard cut/fixings fitted, transponder mount fitted, bearing carrier replaced, exhaust springs and wrap replaced, new manifold holes drilled, sprocket carrier protectors put back on, HT lead replaced, kart cleaned, front and rear chassis height changed, seat stays adjusted, Tillett 40mm washers added (to comply with MSA seat mounting regulations), engine mount adjusted (the mount does not appear to allow the engine to sit perfectly square so the chain is pulled at a very slight angle – need a new mount but the kart pot was empty!), front and read chassis height corrected (stupidly moved it in the opposite direction, even after blogging about rear chassis height!!!) and finally… swapped the front practice tyres over! 🙂

The changing of the tyres was a minor success – the first time I had done this alone although, as the tyres were 200 laps old, it was easier than it might otherwise have been. I was pretty chuffed with myself as I admired the newly fitted tyre – until I realised that I had put it on the same way it had come off! :S

So we’re pretty much all set – the transponder (pleasingly seems to hold full charge even though its not been used since February!), cordless drill, starter battery and GPS watch are all sat on charge on Junior is getting focused (aka upstairs playing Codemasters F1 2013 – I can recommend the Classic Edition :)). I haven’t had a chance to ensure my HT lead is good having borrowed after our problems last time but we should be ok. Wish us luck… 🙂

Purchases since last post: £10 used sprocket puller, £120 three sets of used slicks incl postage, £100 used set of Douglas SE rims (might have paid a little over the norm for these but I really wanted before the race weekend so my ability to wait for something at the right price was lost), £4 10mm deep sprocket.

The second of back-to-back Saturdays. Once again I found myself awake in the early hours, brain totally engaged thinking about the day. Having found the benefits of an early arrival (i.e. plenty of time to get ready for the first session without rushing) to my liking last week, we arrived an hour before the track opened. Unlike last week however, I hadn’t really been able to do as much of the preparation at home the night before owing to the poor weather (the garage has insufficient space to actually work in it and the lighting is awful) so the tyres (a fairly decent ‘new’ used set bought from the forums some time ago) hadn’t been inflated, I hadn’t gotten the new carb gaskets fitted, nor check everything over properly after I had stripped the back end down to dry it last week. The preparation hour was a bit of a rush; I put the new 3l fuel tank on, corrected the kind of mistakes you make when working in the dark (i.e. a front wheel with three wheel nuts but only two bolts used!) and got everything set. We were on the grid when the cadets came off at 10:10.

Our first problem of the day: the kart wouldn’t fire. I gave it a couple of aborted push start attempts but there wasn’t even the hint of it starting. I took it back to the pits and checked the ignition box wire connectors were ok and then checked the spark plug and found that we were not getting a spark. I whipped out the new plug that I had bought in the week for just this purpose and things looked more promising. Hastily, I tossed the old plug in the bin and we went for another attempt at getting on track. Once again the kart is showing no signs of starting so back to the pits again – it seemed the sparking was intermittent. I had used my only spare HT lead at a recent practice at Dunks. Good job that Clay has a shop… only the shop didn’t have one! Fortunately, I was able to borrow one (from my good friend also known as KartingDad’s Karting Dad!), swap the lead over and get the kart starting reliably on the stand and running fine (shame about the plug I threw in the bin full of wasps but never mind).

Junior was on the grid for the start of the second session but only managed three laps before coming in to complain about his brakes. I could see that one pad was rubbing the disc engine-side and there was quite a gap brake-side but assumed, as he had been running ok, that it I could just adjust it at the end of the session. He did another 15 laps but with a slow best time of 39.3s and still complaining about the brake. Back in the pits, I was surprised to see the brake-side pad was rubbing the disc and the gap was now engine-side. If you are thinking “grub screws”, you would be correct: the grub screws had abandoned ship! Pleasingly, I figured that one out straight away too. Disappointingly, this was a mechanic error – I wasn’t overly tightening the grub screws knowing grub screw damage can severely weaken an axle. I have to admit that I hadn’t checked the grub screws at the start of the day so it could well have been that I hadn’t tightened them enough (even for my liking) after refitting the axle. Everything else was still aligned and looking good so it was just the grub screws required – you’d think these would be in stock wouldn’t you? As far as shop stock went, today wasn’t my lucky day so they gave me the only one they had. Having lost a couple at home recently, I only had one spare and my Karting Dad had one also. Cue wandering around the pits trying to buy spares! I managed to get some but it wrote off the remainder of the morning with only 18 laps under our belt and a best (and faulty brake affected) time of 39.1s.

The third session was more like it: 23 laps with a best of 36.6 and lots of time still evident in Junior’s lines. The fourth was better again: running with the camera on-board for first time of the day, Junior managed a 36.5s before the camera mount snapped :S See if you can spot the moment in my YouTube video. I am not convinced this punt on the camera is working – the camera itself is fine but the case and mounts haven’t looked up to the massive vibration that karting poses. For this session we were also running with the MyTach GPS watch. I’ve still not really read up on this but the watch gives you top speed readings and we were looking to test sprocket sizes. Running a 78 sprocket (what we had always run at Clay although I know the quicker guys run a fair bit smaller), we did a fastest lap of 36.57 with a top speed of 64.6mph (ironically analysis at home showed this was not on the fastest lap, which included a top speed of 60.8mph). With our problems seemingly behind us, we switched to a 76 sprocket and ran the GPS again. This time Junior put in a 36.42, the top speed on that lap was 63.8mph and his maximum speed during the session was 64.7mph. Not much in it, I am sure you will agree – I put this down to inconsistency, particularly out of the Top Bend but there was some interesting data in there: he was 3mph quicker down the straight into The Hairpin on the smaller sprocket.

The track then seemed to cool a little and I think my not increasing the tyre pressures a fraction may have cost us a few tenths as we drifted in the 36.6/36.7s laps before we encountered our biggest problem of the day: Junior had been holding up a couple of RotaxMax’s for a few laps and ran wide at The Horseshoe, matey decided to stick his nose up on the outside and, as Junior moved wider to get a line for the bend, they hit – flicking our back end up and causing Junior to run onto the grass. He rejoined the track and ran for another 8 laps. I was very surprised when he came in and I took the chainguard off – the chain looked blackened and dry (it had been freshly lubed) and was missing a few chunks, then I noticed the teeth on the rear sprocket (a brand, spanking new one that day) were wrecked which lead me to a front sprocket with some nice sharp spurs! At this point I needed KartingDad’s Karting Dad (again) as I had no idea how to remove a front sprocket and have learnt I need to buy some new tools :S With hindsight, either of two changes I made during the day may have contributed to this: I removed the sprocket protectors after deciding to use 6 sprocket bolts instead of three (it looked like the front sprocket alignment was a little uneven as the rear sprocket was rotated so I add the extra bolts in case this was the cause and the protectors have three warped holes that no longer easily facilitate the extra bolts) and the chain was running a little looser than I normally have it (on advice!). We went back to the 78 sprocket (now my smallest), a 110 chain (also now my smallest) and fitted a spare front sprocket (thanks again, spares :)).

The track was quieter now and Junior spent the last couple of sessions racing his friends. His lines through the afternoon had really come on – a screech and a lift entering Billies always looks good, taking The Esses with a decent amount of kerb was becoming more of the norm and, although his exit from The Hairpin was still a little tight and he had acquired a new, slower line through The Horseshoe, he was carrying [a little] more speed into and out of the Top Bend. New PB!!! 36.11 🙂 Racing was obviously paying off. For the final session of the day, he spent a few laps following the South West Junior TKM champion 😉 until said champion decided he had enough and wanted to put Junior in his place. Junior didn’t mind though, he was chuffed to bits with another new PB – 36.06s.

So we got off to the worst possible start, endured a pretty expensive day, breakage wise but ended up clocking 166 laps and Junior making further progress.He is definitely quick enough to race. I have no lofty goals/dreams about exactly how competitive he will be, it would be nice to be close enough to the pack to race someone but I doubt that will be the case initially. Whether I am ready to race is another question. I am still making mistakes but I think that is just human nature – I’ll make more than most mechanics, I just need to make sure I learn from them! The troubleshooting is a worry as, if things go wrong, there is no second engine to pull out the trailer, nor is there likely to be for some time. We’re just going to have to see how we get on 🙂

This week I bought a bead breaker, a tyre removal tool and some tyre paste as I wanted to get some fresher rubber on for this weekend and I cannot keep asking another Dad to host me whilst I use all his stuff to change tyres. There are two parts that I really struggle with: getting the tyre removal tool disc into rim (so that you can run the tool around the tyre prior to removal) and then working the tyre onto the rim. I think it’s just my general patheticness as an office boy: getting the removal tool in place is about brute force and working the tyre onto the rim seems to be all about finger strength – and I don’t really have any! Changing the wets last time wasn’t too bad but the new(er) slicks I just put on were some else entirely. Once again I can only claim credit for half the set but I’ll be on my own next time so more practice is inevitable.

I had been meaning to investigate the cause of the problem that caused an early end to our day at Dunkeswell the following day. I needed Junior to be home to help me get the kart off the trailer lid and onto the trolley (the wife refuses after hurting her back the only other time she tried – I won’t take that one any further!) and I had the kart all ready for his teatime arrival so that I could replace the fuel tank and try starting the kart. It was pretty dark when he got home at 9:30pm!!! Barely light enough to get everything replaced/checked never mind starting at 2-stroke go-kart in the front garden at such an unsociable hour. It had to be done though although a couple of quick starting attempts proved fruitless and I quickly threw in the towel.

Ten days passed (is it just me or is the kart easy to ignore when you know you have a problem to resolve?) and I mustered just enough enthusiasm to try again. The carb was holding the fuel ok but the kart just wasn’t firing up. I rested the plug on top of the engine and tried starting again to gauge the health (or otherwise) of the spark – there was no spark! I replaced the spark plug with a couple of the spares although one of the few pitfalls in buying a retirement package is that you’ve no idea as to the quality of the spares. Could three spark plugs all be bad? I made a note to myself to buy a new plug just to keep for troubleshooting and wondered what I could next. I’m still not great at engine problems but the only things I could test were the PVL coil and the ignition HT lead – both of which I had 🙂 The HT lead was the quicker win so that got replaced first. I was very pleasantly surprised to see a spark and then subsequently hear the engine fire up. I couldn’t run it for very long but it started a couple of times. The HT lead did suffer some damage when Junior had a Rotax drive over him but it had been fine until now. Ho hum…

Our race plans have been set back though – we need another good practice day now so it’s looking likely that we’ll head to Clay this week and hope for the best.